The device described by Migler U.S. Pat. No. 4,685,424 for housing monkeys on poles is suitable for small monkeys, such as squirrel monkeys, but would not be suitable for larger and more aggressive monkeys commonly used in laboratories, such as rhesus monkeys or cebus monkeys or baboons, for the following six reasons. First, an unwary passerby or careless caretaker standing near the device may be attacked by these more aggressive primates. Second, a caretaker attempting to change the water bottle or to put food into the food cans may be attacked. Third, a weaker monkey may be attacked and injured seriously by adjacent aggressive monkeys because there is no safe area to which it can retreat. Fourth, when a caretaker attempts to catch a monkey he may be attacked by adjacent monkeys attempting to "protect" the monkey being caught. Fifth, if a monkey breaks loose from its tether it would be free to escape from the device. Sixth, since larger monkeys require more space than smaller monkeys, and therefore a larger apparatus, Migler's unit would be very large, difficult to move, impossible to move through an ordinary doorway, and too large to be cleaned in a conventional cage cleaner.
The present invention, which was disclosed by Migler in Disclosure Document No. 156,079, overcomes these deficiencies. The invention is comprised of a pole-housing device containing two climbing poles to which monkeys can be attached by tethers and are able to make close physical contact with each other without their tethers becoming entangled; perches on which the monkeys may sit; a door or removable panel at each end providing access to each individual monkey; removable side walls; whereby a plurality of such pole-housing devices may be placed alongside each other, connected together by conventional means, and their side walls removed, permitting monkeys in adjacent devices to make close physical contact with each other, and whereby the side walls, or other partitions may be reinserted between adjacent monkeys when it is observed that they fight with each other, thus providing the weaker monkey with a safe area, and whereby the side walls or partitions may also be inserted between monkeys when a caretaker wishes to catch a monkey, thereby preventing his being attacked by adjacent monkeys.